The present study was performed to determine the potential of applying dual-energy subtraction (DES) digital tomo-synthesis to basic physical evaluations. Volumetric X-ray DES digital tomosysnthesis was used to obtain...The present study was performed to determine the potential of applying dual-energy subtraction (DES) digital tomo-synthesis to basic physical evaluations. Volumetric X-ray DES digital tomosysnthesis was used to obtain an image of a detectability phantom (an artificial lesion). The image quality of DES digital tomosynthesis was compared to that of DES radiography. The purpose of this study was to determine enhanced visibility quantified in terms of the contrast- to-noise ratio, figure-of-merit, and root-mean-square error. In the in-focus plane, the image quality is better by DES digital tomosynthesis than by DES radiography. The potential usefulness of DES digital tomosynthesis for evaluating a detectability phantom was demonstrated. Further studies are required to determine the ability of DES digital tomosyn-thesis to quantify the spatial relationships between the artificial lesion components of these devices, as well as to iden- tify lesions with diagnostic consequences.展开更多
With dual-radiopharmaceutical (DR) parathyroid scintigraphy, imaging with 99mTcO4-or 123I-NaI is combined with 99mTc-sestamibi scintigraphy for localization of parathyroid adenomas. The set images are then either visu...With dual-radiopharmaceutical (DR) parathyroid scintigraphy, imaging with 99mTcO4-or 123I-NaI is combined with 99mTc-sestamibi scintigraphy for localization of parathyroid adenomas. The set images are then either visually compared or digitally subtracted to aid in interpretation. While both EANM and SNMMI guidelines recommend use of digital subtraction over visual interpretation alone, to date, the few formal comparisons performed have not demonstrated superiority. The purpose of this investigation is to rigorously assess the added value of digital subtraction over visual interpretation alone using simultaneously-acquired 123I-NaI and 99mTc-sestamibi images. Materials: 90 consecutive patients with DR parathyroid scintigraphy for primary hyperparathyroidism who underwent successful parathyroidectomy were included. DR planar acquisition was performed 15 minutes post injection using 10% dual energy windows. Digital subtraction was subsequently performed using commercially available software. Images were independently reviewed by 3 nuclear medicine trainees and 2 experienced nuclear medicine physicians with and without digital subtraction. Results were compared with surgical and histopathologic findings, which served as ground truth. Results: 90 patients had a total of 91 confirmed parathyroid lesions. All 5 readers had significantly greater sensitivity with digital subtraction compared with visual interpretation alone while specificity was not significantly diminished. Area under the ROC curve was significantly greater with digital subtraction in 3 of 5 readers. Agreement was greater among trainees and experienced physicians when using digital subtraction. Conclusion: Using an optimized DR planar co-imaging technique, digital subtraction significantly improved inter-observer agreement and confidence of interpretation and increased sensitivity, without diminishing specificity.展开更多
Dual-energy X-ray absorptiometry provides two modes of head computed tomography （CT） angiography scanning： neuro-digital subtraction angiography and dual-energy CT angiography （DE-CTA）. Previous studies have comp...Dual-energy X-ray absorptiometry provides two modes of head computed tomography （CT） angiography scanning： neuro-digital subtraction angiography and dual-energy CT angiography （DE-CTA）. Previous studies have compared image quality, radiation exposure, and bone removal between neuro-digital subtraction angiography and DE-CTA. However, the number of cases was relatively small. The present study examined 300 suspected cases of cerebrovascular disease and observed the methods and duration of post-processing, examination time, and data volume. Results demonstrated similar image quality between the two methods, but lower radiation doses and shorter examination time in DE-CTA. DE-CTA allowed for faster and more stable scanning performance and post-processing methods, facilitating accurate and direct diagnosis of cerebrovascular disease.展开更多
文摘The present study was performed to determine the potential of applying dual-energy subtraction (DES) digital tomo-synthesis to basic physical evaluations. Volumetric X-ray DES digital tomosysnthesis was used to obtain an image of a detectability phantom (an artificial lesion). The image quality of DES digital tomosynthesis was compared to that of DES radiography. The purpose of this study was to determine enhanced visibility quantified in terms of the contrast- to-noise ratio, figure-of-merit, and root-mean-square error. In the in-focus plane, the image quality is better by DES digital tomosynthesis than by DES radiography. The potential usefulness of DES digital tomosynthesis for evaluating a detectability phantom was demonstrated. Further studies are required to determine the ability of DES digital tomosyn-thesis to quantify the spatial relationships between the artificial lesion components of these devices, as well as to iden- tify lesions with diagnostic consequences.
文摘With dual-radiopharmaceutical (DR) parathyroid scintigraphy, imaging with 99mTcO4-or 123I-NaI is combined with 99mTc-sestamibi scintigraphy for localization of parathyroid adenomas. The set images are then either visually compared or digitally subtracted to aid in interpretation. While both EANM and SNMMI guidelines recommend use of digital subtraction over visual interpretation alone, to date, the few formal comparisons performed have not demonstrated superiority. The purpose of this investigation is to rigorously assess the added value of digital subtraction over visual interpretation alone using simultaneously-acquired 123I-NaI and 99mTc-sestamibi images. Materials: 90 consecutive patients with DR parathyroid scintigraphy for primary hyperparathyroidism who underwent successful parathyroidectomy were included. DR planar acquisition was performed 15 minutes post injection using 10% dual energy windows. Digital subtraction was subsequently performed using commercially available software. Images were independently reviewed by 3 nuclear medicine trainees and 2 experienced nuclear medicine physicians with and without digital subtraction. Results were compared with surgical and histopathologic findings, which served as ground truth. Results: 90 patients had a total of 91 confirmed parathyroid lesions. All 5 readers had significantly greater sensitivity with digital subtraction compared with visual interpretation alone while specificity was not significantly diminished. Area under the ROC curve was significantly greater with digital subtraction in 3 of 5 readers. Agreement was greater among trainees and experienced physicians when using digital subtraction. Conclusion: Using an optimized DR planar co-imaging technique, digital subtraction significantly improved inter-observer agreement and confidence of interpretation and increased sensitivity, without diminishing specificity.
文摘Dual-energy X-ray absorptiometry provides two modes of head computed tomography （CT） angiography scanning： neuro-digital subtraction angiography and dual-energy CT angiography （DE-CTA）. Previous studies have compared image quality, radiation exposure, and bone removal between neuro-digital subtraction angiography and DE-CTA. However, the number of cases was relatively small. The present study examined 300 suspected cases of cerebrovascular disease and observed the methods and duration of post-processing, examination time, and data volume. Results demonstrated similar image quality between the two methods, but lower radiation doses and shorter examination time in DE-CTA. DE-CTA allowed for faster and more stable scanning performance and post-processing methods, facilitating accurate and direct diagnosis of cerebrovascular disease.
